In September, we told you about researchers that had located the genes for telomerase, a protein that might help cells live longer. Now, related research from the University of Texas Southwestern Medical Center and the Geron Corporation have confirmed that the presence of telomerase actually does make ordinary cells live longer. Their work may offer new ways to help cells live longer - or, alternately, to make long-lived cancer cells start to die.

The telomere is a cap of repeating genes at the tip of the chromosome. Every time the cell divides, the chromosome is duplicated - and its telomeres get shorter. The number of times a cell can divide is determined by its chromosomes’ telomere length; when the telomere becomes too short the cell can no longer divide. Some specialized cells, like sperm cells, must divide more times than their telomeres might allow. These cells produce telomerase, a compound that rebuilds their telomeres. Cancer cells also often produce telomerase, which makes them “immortal.”

The chromosomes are x-shaped bundles of genetic material in the cell nucleus. At the end of each chromosome is a cap called a telomere, like the plastic tip on a shoelace. Telomerase repairs the tips of chromosomes, allowing cells to keep dividing and live longer.

In the current study, researchers added telomerase to human cells that do not usually produce it. They found that the cells containing telomerase were able to divide up to 20 times more than the non-telomerase containing cells. The researchers are now looking into possible uses for their findings, from treatment of some of the diseases of aging to producing better cell samples for use in the lab. The team has also been looking, without success, for possible ways to block telomerase production in cancer cells.

On this segment of Science Friday, we’ll take a look at the team’s findings, and see what implications they could have for the world of medicine.

Then.forgetfulness. People have known for quite a while about genes that help to suppress tumors, keeping cancerous cells in check. Now, however, researchers say that there may be genes that suppress memories as well—and these genes aren’t all bad.

Memory suppressor genes, argue the team from the Howard Hughes Medical Institute at Columbia University, aid in regulating long-term memory storage. They allow you to remember important details, like what your car looks like, but forget less important details - like the license plate numbers of the thirty other cars parked nearby. Memory suppressor genes may also help to clear out the cobwebs in the synapses prior to learning new material.

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